The invention relates to a sprinkler or similar subassembly for discharging fluid, with which the fluid, usually water, can be discharged over a relatively long distance of e.g. several meters from the sprinkler head or outlet, so that it covers a predetermined sprinkling or watering field, which is usually positioned roughly horizontally or by a horizontal position forms a measurement base. For this purpose, the water is discharged under pressure from the sprinkler outlet over a free jet path, usually a parabolic projection path, and from the outlet, there is no further contact with or direct guidance of the fluid jet by the sprinkler.
For watering vegetation, it is possible to use sprinklers with a fixed outlet during operation, or those in which the fluid jet is given a transverse movement directed at right angles to its longitudinal direction e.g. in that the sprinkler head performs a movement roughly parallel or at right angles to the sprinkling field, such as a continuous unidirected and/or a reciprocating rotary or axial movement. In order to discharge the fluid jet as far as possible, as compared with an approximately horizontal or approximately vertically upwardly or downwardly directed orientations of the outlet, preference is given to an upwardly sloping orientation under an angle of approximately 30.degree. to 45.degree.. For example, by means of a rod-like or upwardly extendable construction of the sprinkler head, it is possible to obtain a relatively high position of the outlet with respect to or over the sprinkling field. Such a sprinkler is e.g. described in European patent application 410,198 or European patent application 362,559, to which reference is made in the present invention for incorporating their features and actions.
If it is intended to discharge the fluid jet, with a supply pressure given by a restrictor or the pressure in the water mains, over a considerable distance of e.g. more than 3, 5 or 10 meters, then the shape of the nozzle outlet and the fluid paths leading thereto or the channel portions of the fluid guide are appropriately chosen in such a way that a linear, calm flow is supplied to the nozzle outlet and the fluid jet leaves the nozzle outlet as a so-called concentrated jet, which leaves-the fluid outlet in closely bundled, focused or concentrated form without any significant spraying and remains in this way for several meters. This concentrated jet only fans out at a considerable distance from the fluid outlet and waters a sprinkling field of predetermined surface size with an average watering density per surface unit, which is appropriately substantially constant over the sprinkling field.
Between the sprinkling field and the sprinkler, there is usually no significant sprinkling or watering, so that in said near field, the sprinkling density is much lower than in the true sprinkling field. This can admittedly be counter-acted by a corresponding, e.g. asymmetrical design of the sprinkler outlet, but there is then a reduced maximum range of the fluid or concentrated jet, because part of the fluid jet is branched off as a spray jet for the near area.
Much the same occurs if the outlet or the point of final contact of the fluid jet with the sprinkler is formed by a jet disturbance member, which is rhythmically moved into the concentrated jet and consequently on each occasion brings about a spraying action for the near area. The short spray pulses are generally not sufficient to water, in the same way as the concentrated jet sprinkling field, the near area or the field between the sprinkling field of the concentrated jet and the sprinkler with roughly the same watering density. Even if the concentrated jet or the sprinkler outlet is moved from one inoperative position to the next by a jerky transverse movement, admittedly said pulse movement slightly reduces the range of the fluid jet, but not in such a way that the near area is appropriately watered.